青海省兴海县大河坝地区铜银多金属矿成矿地质特征研究

Study on Cu,Ag Polymetallic Deposit Metallogenic Geological Features in Daheba Area,Xinghai County,Qinghai Province

青海省大河坝地区位于东昆仑造山带和西秦岭造山带两大造山带的交汇部位,区内成矿地质条件优越。研究结果表明,工作区中部主要存在两条主干矿化构造蚀变带(Ⅰ、Ⅱ号矿化构造蚀变带)和三条次级矿化构造蚀变带(Ⅱ-1、Ⅱ-2和Ⅱ-3号矿化构造蚀变带)。I号矿化带中施工的ZK12见15条铜矿体、3条铅(银)矿体、1条金矿体;铜矿体累计视厚度123. 45m,Cu平均品位0. 50～1. 21×10-2。矿体分布受构造控制。空间上呈陡倾状或以透镜状雁行式产出。

The Daheba area in Qinghai Province is situated at the intersections of eastern Kunlun orogenic belt and western Qinling orogenic belt with advantageous metallogenic geological conditions.The studied results have shown that there are two backbone metallization tectonic alteration zones(ⅠandⅡ)and three secondary metallization tectonic alteration zones(Ⅱ-1,Ⅱ-2 andⅡ-3)existed in the middle of working area.The borehole ZK12 drilled in metallization zoneⅠhas intersected 15 copper orebodies,3 lead(silver)orebodies and 1 gold orebody.The cumulative apparent thickness of copper orebodies is 123.45m,average grade 0.50~1.21×10^-2.Orebody distribution is controlled by structures.Spatially presents steeply dipping or en echelon arranged lenses patterns.